Eri Ninamori (ニナモリ・エリ?, Ninamori Eri) is the daughter of the mayor of Mabase and the president of Naota's sixth grade class. Like Naota she is obsessed with acting grown-up, but she often loses her composure when angry or excited. Ninamori hides her frustration with her father's sex scandal, and rigs an election for the school play so that she gets the lead role while Naota gets cast opposite her, hinting that she has a crush on him.
Eri Ninamori, 12, is Naota's classmate. In the series, she is referred to as 'Ninamori,' her family name. She is the daughter of the mayor of Mabase and is class president. Ninamori has N.O. powers as well, though they only manifest once when Naota hit his head on hers. In this instance, Naota's third robot, which expresses at first as "cat ears", transfers to her instantly when the Medical Mechanica factory's siren blows. In the manga, an octopus-like robot comes forth, before running away with Naota, and appears very little after that until it helps her save Naota from an angered Haruko.
Ninamori projects a proper, even slightly stuck-up personality, and conceals personal information to an almost obsessive degree; she does not even let her classmates know that she needs corrective lenses, instead wearing contacts while at school. Even with her class president status, however, Ninamori isn't above breaking the rules to get what she wants. She rigs the voting during the casting for the school play in order to get the lead role and have Naota cast opposite her, which hints at her crush on Naota. Other hints are her expressed dislike of Mamimi and Haruko, letting him see her wearing glasses, and a final scene with Naota by a vending machine that mirrors Mamimi and Naota's early-series interactions. Ninamori is also highly intelligent, if a little jaded. Much like Naota, Ninamori attempts to act mature, and although her parents' problems trouble her deeply, she refuses to admit it until near the end of the series. During the final episode, during gym practice, she tells her classmates Masashi Masamune and Gaku Manabe that she had finally talked to her parents, letting them see her cry, and then performs an impressive high jump which her classmates and teacher applaud - a possible representation of how Ninamori has achieved real emotional maturity, something which Naota had yet to accomplish.
Ninamori is a bit tall for her age, tall enough that Naota's pajamas are a little short for her. She has dark, blue-green eyes and purple hair. For the first half of the series, she wears her hair long and straight. At the end of the third episode, it is cut to chin-length, and she styles it with accessories or in short pigtails for the rest of the series. In her last scene in the final episode, her hair has grown longer and she wears it in braids. Ninamori wears different clothes in all of her appearances and has many outfits throughout the series.
Ninamori's glasses are her most significant possession. Although she is only shown wearing them in episode 3, they represent her true self and the only person she allows to see her wearing them is Naota. At the end of the episode, when the school play is about to start, he sees her wearing glasses on stage, but she pokes her finger through the frames to show they have no lenses. These fake glasses are not the same as the ones she wore earlier in the episode, which have real lenses.
Ninamori seems to have a crush on Naota, first indicated by playful teasing and jealousy towards Mamimi. In the third episode, she goes so far as to rig the votes just to have him cast as her co-star in the class play, and even confides the secret to him when they are alone. She feels a meaningful connection to him, noticing their shared distaste for the fake maturity that adults emulate throughout the series, but mistakenly attributes his reason for developing this view. This mistake is the reason she selected him and rigged his votes, as the character he will play displays Ninamori's view. She compares him directly to his character when opening up to him via the quote, "He hides who he really is and pretends to be someone else forever, but in time becomes that person, so his lie becomes the truth, see? He transcends the mask. Well, don't you get it? That's how he finds happiness." However, Naota can't understand that reasoning because he didn't develop his worldview that way. While Ninamori gained it from the chaos that is pretending to be the successful daughter of a mayor who cheats on his wife, Naota simply hit a wall with maturity that created a disdain for people who fake what he desires. The misunderstanding results in a break in the romantic tension between them and later culminates in their fight as their respective immaturity clashes. Notwithstanding, she values the understanding they have and gains a better grasp of her own struggles because of him. Naota, meanwhile, treats her with a bit more respect than he does Mamimi or Haruko, sympathizing with her family issues and calling her "very grown up" at one point. They do not take any further steps toward romance, however, until the final episode.
Ninamori does not meet Haruko until the third episode, and her first impression of her is a strongly negative one. However, although it's clear Ninamori has some jealousy of her relationship with Naota, she doesn't do or say much about it later.
Ninamori does not interact with Mamimi at all, but from hearing about her being called "Naota's wife" and seeing them together, she is quick to judge her as a ditzy airhead. Her opinion of Mamimi seems to change slightly when she notices how Naota's closeness with Haruko is hurting her.
Gaku and Masashi are probably the closest friends Ninamori has besides Naota. They call her "Ninamo", she hangs out with them during and after school, and even gets a part-time job making deliveries with them in the fifth episode. By the end of the final episode, they start showing signs of being attracted to her, though she still seems more interested in Naota.
Abilities and PowersEdit
Ninamori is a typical girl until the Medical Mechanica factory's siren goes off in episode three. Suddenly, the cat-like ears signaling Naota's N.O. activity throughout the episode transfer over to her head and a robot partially emerges from it. While stuck in her head, it has complete control over her and makes her eyes glow red. She begins kicking Naota and Canti with rapid precision, and fighting Haruko when she attacks. In this state, her legs are strong enough to fend off blows from Haruko's guitar and send people flying on impact.
Aside from becoming part of the Masamune delivery service, asking questions and hanging out with Naota on some occasions, Ninamori's character arc takes place entirely in Marquis de Carabas.
- In an interview with director Tsurumaki, he mentioned how Ninamori's appearance changes with every scene she's in, saying that Nobutoshi Ogura favored her design and had fun altering it in subsequent episodes.